Results of anterior tucking of the superior oblique muscle tendon in bilateral fourth nerve palsy.

BACKGROUND: Bilateral fourth nerve palsy is characterised by excyclotorsion, which can be corrected by reinforcement of the anterior tendon fibres of the superior oblique muscle. PATIENTS AND METHODS: A retrospective study of 40 consecutive patients with bilateral acquired fourth nerve palsy operated by a selective tuck of the anterior portion of the superior oblique tendon between 1994 and 2012 was undertaken. Horizontal, vertical and torsional deviations were measured in 9 diagnostic positions of gaze and the field of binocular single vision was evaluated with the Harms tangent screen. Postoperative follow-ups took place at 1 week, 6 months, and ≥3 years. RESULTS: Preoperative mean excyclotorsion was 9° in the primary position and 15° in downgaze. These values decreased to 2° and 5° 6 months after surgery, and 2.5° and 6° at ≥3 years. Immediate post-operative incyclotorsion in upgaze (28 patients) and Brown syndrome (15 patients) regressed spontaneously. The median score of field of binocular single vision improved from 4% preoperatively to 76% postoperatively. CONCLUSIONS: The selective tuck of the anterior tendon fibers of the superior oblique tendon enables an efficient and long-lasting correction of the ocular torsion induced by bilateral trochlear palsy.

Torsional strabismus and vertical rectus muscle surgery in thyroid eye disease.

PURPOSE: To assess the torsional component in patients with vertical strabismus due to thyroid eye disease (TED) and its course after vertical rectus muscle surgery. PATIENTS AND METHODS: Retrospective chart review of patients undergoing vertical strabismus surgery for TED between 1998 and 2017, having undergone pre- and postoperative Harms tangent screen examination. RESULTS: Forty patients (27 women) were identified. A torsional component was present in all patients. Thirty-three patients had a mean excyclotorsion of 4.5° in primary position, increasing to 8.2° in upgaze, associated with restricted elevation. Inferior rectus muscle recession (n=29) reduced the excyclotorsion in all cases. A 4.4° mean incyclotorsion was present in primary position in 7 cases, increasing to 7.1° in downgaze. Superior rectus muscle recession reduced the incyclotorsion in 5/6 cases. The torsional surgical dose-effect relationship was correlated with the amount of preoperative torsion. The field of binocular single vision improved from 6.5% preoperatively to 71.1% after surgery. CONCLUSIONS: Ocular torsion is common in vertical strabismus secondary to TED and is significantly improved by vertical rectus muscle surgery alone. Surgery should be planned according to vertical deviation and motility limitation, and vertical rectus muscles surgery should be considered the first line of treatment, with selective oblique muscle surgery as a second-line option, which was unnecessary in our series.

Anterior segment angiography in strabismus surgery.

BACKGROUND: Anterior ciliary arteries travelling along recti muscles provide anterior segment vascularization, which can be compromised by surgery involving more than 2 muscles. PATIENTS AND METHODS: We studied retrospectively the files of 10 patients in whom a fluorescein angiography of the iris had been performed as a pre-operative assessment prior to a second or third oculomotor surgery. RESULTS: The median age of the patients was 47.5 years (range 15 to 73 years). Relative iris ischemia was present in 4 patients following multiple surgeries, none of them presenting any general cardiovascular risk. The initial surgical protocol was modified according to angiographic results in these 4 patients. CONCLUSION: When further surgery has to be performed on previously multi-operated patients, anterior segment angiography can be useful in the planning of surgery in order to minimize the risks of anterior segment ischemia.

[Ophthalmology. Stereopsis: back in the spotlight]. / Ophtaltmologie. La stéréoscopie sur le devant de la scène.

Stereopsis was brought to the fore by its stunning development in a virtual element, in movies or game devices. The mechanisms used to produce 3D artificially are very similar to those involved in natural depth perception. They include binocular stereopsis, generated by the simultaneous perception of two images with a slight horizontal shift, together with the interpretation of monocular clues (perspective, distribution of light and shadow,...). Because virtual 3D uses the same mechanisms as natural perception, there is no reason to believe that 3D movies might be dangerous for the eyes.

Complement facilitates early prion pathogenesis.

New-variant Creutzfeldt-Jakob disease and scrapie are typically initiated by extracerebral exposure to the causative agent, and exhibit early prion replication in lymphoid organs. In mouse scrapie, depletion of B-lymphocytes prevents neuropathogenesis after intraperitoneal inoculation, probably due to impaired lymphotoxin-dependent maturation of follicular dendritic cells (FDCs), which are a major extracerebral prion reservoir. FDCs trap immune complexes with Fc-gamma receptors and C3d/C4b-opsonized antigens with CD21/CD35 complement receptors. We examined whether these mechanisms participate in peripheral prion pathogenesis. Depletion of circulating immunoglobulins or of individual Fc-gamma receptors had no effect on scrapie pathogenesis if B-cell maturation was unaffected. However, mice deficient in C3, C1q, Bf/C2, combinations thereof or complement receptors were partially or fully protected against spongiform encephalopathy upon intraperitoneal exposure to limiting amounts of prions. Splenic accumulation of prion infectivity and PrPSc was delayed, indicating that activation of specific complement components is involved in the initial trapping of prions in lymphoreticular organs early after infection.

[Could the screening of autoimmune diseases be simplified?]. / Dépistage d'une vascuuite ou d'une collagénose: tentative de simplification.

Autoimmune diseases (AD) represent usually a big challenge for the general physician (GP) and are often under diagnosed because of their rarity and their complex clinical symptoms. Even though AD are rapidly suspected, the GP is often exposed to the difficulty of screening and the complexity of the various biological tests at his disposal. This article propose the way to simplify the primary diagnostic approach of AD which often need a further specialized counseling necessary to determine the therapy.

Influence of change in body position on choroidal blood flow in normal subjects.

AIM: To compare subfoveal choroidal blood flow (ChBF) in sitting and supine positions in normal volunteers. METHODS: ChBF was measured with laser Doppler flowmetry in 22 healthy volunteers of mean (SD) age 24 (5) years. Six independent measurements of ChBF were obtained in one randomly selected eye of each subject while seated. The subjects then assumed a supine position for 30 minutes and a new series of six measurements was obtained. The mean values of the two series were calculated. Systemic brachial artery blood pressure and intraocular pressure were measured in the sitting and supine positions. Ocular perfusion pressure (OPP) was calculated based on formulae derived from ophthalmodynamometric studies. The influence of changing OPP during change in body posture on the change in ChBF was assessed by linear regression analysis. RESULTS: ChBF decreased by 6.6% (p = 0.0017) in the supine position. The estimated ophthalmic blood pressure in the supine position was adjusted to obtain a result of no change in OPP for no change in ChBF, yielding a mean decrease in the estimate of OPP of 6.7% (p = 0.0002). The necessary adjustment for the estimate of OPP in the supine position suggested a marked buffering of the change in perfusion pressure by the carotid system. The relative decrease in OPP correlated significantly with the relative decrease in ChBF (R(2) = 0.20; p = 0.036) with a slope for the regression line of 1.04. CONCLUSIONS: The comparable degree of change in ChBF and OPP and the linear relationship between the two parameters suggest a passive response of the choroidal circulation to a change in posture. In contrast, the carotid system seems to control the gradient in perfusion pressure closely between the heart and its branches.

Ticlopidine-induced interstitial pulmonary disease: a case report.

We report a case of interstitial pulmonary disease that occurred together with lymphocytic colitis during treatment with ticlopidine. The drug was prescribed for transient ischemic cerebrovascular accidents. Ticlopidine treatment was stopped, and a prolonged course of prednisone was necessary to treat the pulmonary and intestinal symptoms. So far, few cases of pulmonary side effects caused by ticlopidine have been reported. This case is unique in that interstitial lung disease evolved in parallel with colitis and caused severe hypoxemia. Special care should be taken when pulmonary symptoms appear in association with ticlopidine treatment.

[Management of motility disorders secondary to iatrogenic orbital fracture during endoscopic sinus surgery]. / Prise en charge des troubles oculomoteurs après effraction iatrogène de l'orbite au cours d'interventions sinusiennes endoscopiques.

PURPOSE: Orbital wall fracture may occur during endoscopic sinus surgery, resulting in oculomotor disorders. We report the management of four cases presenting with this surgical complication. METHODS: A non-comparative observational retrospective study was carried out on four patients presenting with diplopia after endoscopic ethmoidal sinus surgery. All patients underwent full ophthalmologic and orthoptic examination as well as orbital imaging. RESULTS: All four patients presented with diplopia secondary to a medial rectus lesion confirmed by orbital imaging. A large horizontal deviation as well as limitation of adduction was present in all cases. Surgical management consisted of conventional recession-resection procedures in three cases and muscle transposition in one patient. A useful field of binocular single vision was restored in two of the four patients. CONCLUSION: Orbital injury may occur during endoscopic sinus surgery and cause diplopia, usually secondary to medial rectus involvement due to the proximity of this muscle to the lamina papyracea of the ethmoid bone. Surgical management is based on orbital imaging, duration of the lesion, evaluation of anterior segment vasculature, results of forced duction testing and intraoperative findings. In most cases, treatment is aimed at the symptoms rather than the cause, and the functional prognosis remains guarded.

Region-specific deletions of RIM1 reproduce a subset of global RIM1α(-/-) phenotypes.

The presynaptic protein RIM1α mediates multiple forms of presynaptic plasticity at both excitatory and inhibitory synapses. Previous studies of mice lacking RIM1α (RIM1α(-/-) throughout the brain showed that deletion of RIM1α results in multiple behavioral abnormalities. In an effort to begin to delineate the brain regions in which RIM1 deletion mediates these abnormal behaviors, we used conditional (floxed) RIM1 knockout mice (fRIM1). By crossing these fRIM1 mice to previously characterized transgenic cre lines, we aimed to delete RIM1 selectively in the dentate gyrus (DG), using a specific preproopiomelanocortin promoter driving cre recombinase (POMC-cre) line , and in pyramidal neurons of the CA3 region of hippocampus, using the kainate receptor subunit 1 promoter driving cre recombinase (KA-cre). Neither of these cre driver lines was uniquely selective to the targeted regions. In spite of this, we were able to reproduce a subset of the global RIM1α(-/-) behavioral abnormalities, thereby narrowing the brain regions in which loss of RIM1 is sufficient to produce these behavioral differences. Most interestingly, hypersensitivity to the pyschotomimetic MK-801 was shown in mice lacking RIM1 selectively in the DG, arcuate nucleus of the hypothalamus and select cerebellar neurons, implicating novel brain regions and neuronal subtypes in this behavior.

Management of diplopia secondary to neurosurgical injury of the orbital roof.

BACKGROUND: Diplopia related to neurosurgical procedures is often consecutive to oculomotor nerve lesions. We hereby report an oculomotor dysfunction secondary to an orbital roof effraction and its treatment. HISTORY AND SIGNS: Following surgery for a left anterior communicating artery aneurysm, a 45-year-old woman reported vertical diplopia associated with a left orbital hematoma. The diagnosis of third cranial nerve palsy was excluded by orbital imaging which revealed an orbital roof defect with incarceration of the levator palpebrae and superior rectus. THERAPY AND OUTCOME: As neurosurgeons advised against muscle adhesiolysis, diplopia was corrected by a two-step procedure on the oculomotor muscles. We first corrected horizontal and torsional deviations by operating on the healthy eye, before correcting the vertical deviation on the fellow eye. This two-step extraocular muscle surgery allowed restoration of binocular single vision in a useful field of gaze. CONCLUSIONS: Diplopia can occur as a rare orbital complication during neurosurgical procedures. Surgery of extraocular muscles can provide good functional results.